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Does order of where clauses matter in SQL?
Let's say I have a table called PEOPLE having 3 columns ID, LastName, FirstName , none of these columns are indexed.
LastName is more unique, and FirstName is less unique.
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Order data frame rows according to vector with specific order
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236
Try match:
df <- data.frame(name=letters[1:4], value=c(rep(TRUE, 2), rep(FALSE, 2)))
target...
req.query and req.param in ExpressJS
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edited Aug 30 '13 at 3:20
answered Aug 30 '13 at 2:55
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Aligning a float:left div to center?
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3
Just in case anyone is struggling with the spaces that appear in between the elements, remove the the whitespace in your code by defining yo...
Why does “,,,” == Array(4) in Javascript?
...ring()
"a,b,c"
How the comparison works is described in section 11.9.3 of the specification. There you will see (x == y):
8. If Type(x) is either String or Number and Type(y) is Object,
return the result of the comparison x == ToPrimitive(y).
(arrays are objects in JavaScript)
and ...
How to add an extra column to a NumPy array
...p.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstack((a,np.zeros((a.shape[0],1))))
10000 loops, best of 3: 19.6 us per loop
In [27]: %timeit b = np.zeros((a.shape[0],a.shape[1]+1)); b[:,:-1] = a
10000...
Installing specific laravel version with composer create-project
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edited Apr 14 '15 at 13:14
answered May 20 '14 at 8:15
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Sorting data based on second column of a file
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346
You can use the sort command:
sort -k2 -n yourfile
-n, --numeric-sort compare according to s...
Getting an empty JQuery object
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edited Jun 23 '11 at 5:44
answered May 22 '09 at 11:03
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